1. Field of the Invention
The preferred embodiment relates to systems and methods for providing video program material to subscribers, and in particular to a method and system for providing extended program guides to subscribers.
2. Description of the Related Art
Television programs are distributed to viewers by a variety of broadcasting methods. These methods include traditional analog broadcast television (National Television Systems Committee or “NTSC” standard), the upcoming digital broadcast television (Advanced Television Systems Committee or “ATSC” standard), cable television (both analog and digital), satellite broadcasting (both analog and digital), as well as other methods. These methods allow channels of television content to be multiplexed and transmitted over a common transmission medium.
In recent years, there has been an increasing demand for video distribution systems to provide more program channels. In digital satellite systems, this may be accomplished in many ways. One way of increasing the number of available channels is to increase the compression or decrease the error correction provided in the broadcast signal of existing satellites. Another way of increasing the number of available channels is to increase the bandwidth of the downlink from the satellite to the subscribers' receivers. Unfortunately, this technique is difficult to accomplish with existing (legacy) satellites and in a way that is compatible with existing (legacy) receivers.
As a result, video distribution systems have evolved to include additional satellites to broadcast additional program material to subscribers. Typically, satellites broadcasting these enhanced services are deployed in geosynchronous orbits in orbital locations proximate to those of the legacy satellites. This allows a single antenna to receive signals from both satellites with little or no physical scanning.
Electronic program guides for television programming are known in the art. Such program guides typically include a viewer channel number that identifies the stream of television content offered by a content provider and a description of each media program associated with the channel number. Program guide information is typically transmitted along with the television content, and typically also includes schedule information for display on users' televisions. The schedule information informs users what television programs are currently on, and what television programs will be shown in the near future.
Providing electronic program guides for the additional viewer channels carried by the multiple satellite video distribution system has become problematic. Typically, each satellite used in such systems transmits program guide information describing only those viewer channels carried by the satellite, and do so at regular and frequent intervals (e.g. every 5 seconds). This allows a new subscriber to receive program guide information for the satellite they are turned to within a short period of time after setting up and activating the receiver station. However this has its disadvantages. Most notably, in multiple-satellite video distribution systems, when the subscriber requests program guide information regarding a viewer channel broadcast by a different satellite than the currently tuned viewer channel, the subscriber can experience a delay of several seconds before the program guide information is displayed.
For example, the system disclosed in U.S. Pat. Nos. 5,550,576 and 5,923,362, which are hereby incorporated by reference herein, disclose a system wherein a coordinator at the subscriber location collects program guide information from a number of sources and sorts and merges the program guide information into a single guide. However this solution requires multiple tuners to simultaneously receive program guide information from two separate satellites or the above-described delay will result when switching from one program source to another.
It is possible to simply repeat the program guide information from all satellites on one channel. Such a system is described in U.S. Pat. No. 6,072,983, which is hereby incorporated by reference herein. However, the system described in the '983 patent either requires additional downlink bandwidth or must extend the period of time between program guide updates. It also may presents program guide information about viewer channels which should not be received by subscribers with legacy receivers. For such subscribers, the numerous additional viewer channels can become a nuisance, since they take up space on the program guide presented to the subscriber and serve no useful purpose.
What is needed is a method and apparatus to integrate program guide information for media programs broadcast by a plurality of satellites, and to provide such program guide information only to media subscribers who are capable of receiving the viewer channels described by the integrated program guide without wasting bandwidth or providing the program information on a delayed basis. The preferred embodiment satisfies that need.